/**

    @file WiFiMulti.cpp
    @date 16.05.2015
    @author Markus Sattler

    Copyright (c) 2015 Markus Sattler. All rights reserved.
    This file is part of the esp8266 core for Arduino environment.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/

#include "WiFiMulti.h"
#include <limits.h>
#include <string.h>
#include "Seeed_atUnified.h"

WiFiMulti::WiFiMulti() {
}

WiFiMulti::~WiFiMulti() {
    for (uint32_t i = 0; i < APlist.size(); i++) {
        WifiAPlist_t entry = APlist[i];
        if (entry.ssid) {
            free(entry.ssid);
        }
        if (entry.passphrase) {
            free(entry.passphrase);
        }
    }
    APlist.clear();
}

bool WiFiMulti::addAP(const char* ssid, const char* passphrase) {
    WifiAPlist_t newAP;

    if (!ssid || *ssid == 0x00 || strlen(ssid) > 31) {
        // fail SSID too long or missing!
        log_e("[WIFI][APlistAdd] no ssid or ssid too long");
        return false;
    }

    if (passphrase && strlen(passphrase) > 63) {
        // fail passphrase too long!
        log_e("[WIFI][APlistAdd] passphrase too long");
        return false;
    }

    newAP.ssid = strdup(ssid);

    if (!newAP.ssid) {
        log_e("[WIFI][APlistAdd] fail newAP.ssid == 0");
        return false;
    }

    if (passphrase && *passphrase != 0x00) {
        newAP.passphrase = strdup(passphrase);
        if (!newAP.passphrase) {
            log_e("[WIFI][APlistAdd] fail newAP.passphrase == 0");
            free(newAP.ssid);
            return false;
        }
    } else {
        newAP.passphrase = NULL;
    }

    APlist.push_back(newAP);
    log_i("[WIFI][APlistAdd] add SSID: %s", newAP.ssid);
    return true;
}

uint8_t WiFiMulti::run(uint32_t connectTimeout) {
    int8_t scanResult;
    uint8_t status = WiFi.status();
    if (status == WL_CONNECTED) {
        for (uint32_t x = 0; x < APlist.size(); x++) {
            if (WiFi.SSID() == APlist[x].ssid) {
                return status;
            }
        }
        WiFi.disconnect(false, false);
        delay(10);
        status = WiFi.status();
    }

    scanResult = WiFi.scanNetworks();
    if (scanResult == WIFI_SCAN_RUNNING) {
        // scan is running
        return WL_NO_SSID_AVAIL;
    } else if (scanResult >= 0) {
        // scan done analyze
        WifiAPlist_t bestNetwork { NULL, NULL };
        int bestNetworkDb = INT_MIN;
        uint8_t bestBSSID[6];
        int32_t bestChannel = 0;

        log_i("[WIFI] scan done");

        if (scanResult == 0) {
            log_e("[WIFI] no networks found");
        } else {
            log_i("[WIFI] %d networks found", scanResult);
            for (int8_t i = 0; i < scanResult; ++i) {

                String ssid_scan;
                int32_t rssi_scan;
                uint8_t sec_scan;
                uint8_t* BSSID_scan;
                int32_t chan_scan;

                WiFi.getNetworkInfo(i, ssid_scan, sec_scan, rssi_scan, BSSID_scan, chan_scan);

                bool known = false;
                for (uint32_t x = 0; x < APlist.size(); x++) {
                    WifiAPlist_t entry = APlist[x];

                    if (ssid_scan == entry.ssid) { // SSID match
                        known = true;
                        if (rssi_scan > bestNetworkDb) { // best network
                            if (sec_scan == WIFI_AUTH_OPEN || entry.passphrase) { // check for passphrase if not open wlan
                                bestNetworkDb = rssi_scan;
                                bestChannel = chan_scan;
                                memcpy((void*) &bestNetwork, (void*) &entry, sizeof(bestNetwork));
                                memcpy((void*) &bestBSSID, (void*) BSSID_scan, sizeof(bestBSSID));
                            }
                        }
                        break;
                    }
                }

                if (known) {
                    log_d(" --->   %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) %c", i, chan_scan, BSSID_scan[0], BSSID_scan[1],
                          BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5], ssid_scan.c_str(), rssi_scan,
                          (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*');
                } else {
                    log_d("       %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) %c", i, chan_scan, BSSID_scan[0], BSSID_scan[1],
                          BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5], ssid_scan.c_str(), rssi_scan,
                          (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*');
                }
            }
        }

        // clean up ram
        WiFi.scanDelete();

        if (bestNetwork.ssid) {
            log_i("[WIFI] Connecting BSSID: %02X:%02X:%02X:%02X:%02X:%02X SSID: %s Channal: %d (%d)", bestBSSID[0], bestBSSID[1],
                  bestBSSID[2], bestBSSID[3], bestBSSID[4], bestBSSID[5], bestNetwork.ssid, bestChannel, bestNetworkDb);

            WiFi.begin(bestNetwork.ssid, bestNetwork.passphrase, bestChannel, bestBSSID);
            status = WiFi.status();

            auto startTime = millis();
            // wait for connection, fail, or timeout
            while (status != WL_CONNECTED && status != WL_NO_SSID_AVAIL && status != WL_CONNECT_FAILED
                    && (millis() - startTime) <= connectTimeout) {
                delay(10);
                status = WiFi.status();
            }

            switch (status) {
                case WL_CONNECTED:
                    log_i("[WIFI] Connecting done.");
                    log_d("[WIFI] SSID: %s", WiFi.SSID().c_str());
                    log_d("[WIFI] IP: %s", WiFi.localIP().toString().c_str());
                    log_d("[WIFI] MAC: %s", WiFi.BSSIDstr().c_str());
                    log_d("[WIFI] Channel: %d", WiFi.channel());
                    break;
                case WL_NO_SSID_AVAIL:
                    log_e("[WIFI] Connecting Failed AP not found.");
                    break;
                case WL_CONNECT_FAILED:
                    log_e("[WIFI] Connecting Failed.");
                    break;
                default:
                    log_e("[WIFI] Connecting Failed (%d).", status);
                    break;
            }
        } else {
            log_e("[WIFI] no matching wifi found!");
        }
    } else {
        // start scan
        log_d("[WIFI] delete old wifi config...");
        WiFi.disconnect();

        log_d("[WIFI] start scan");
        // scan wifi async mode
        WiFi.scanNetworks(true);
    }

    return status;
}
